Computer networks have been developed to allow files to be shared among a number of remote users or clients. In the past, computer networks were designed to support single computer types with a limited range of file systems. In prior systems, a dedicated file server is required for each type of computer. Recently, several types of computer systems have appeared on the market, each of which have file systems which are not compatible with other systems. As many alternate computer systems now coexist in many office environments, it is highly desirable to provide a method and means for allowing these systems to share files over a computer network.
One approach to networking diverse computer systems is to provide discrete file servers for each type of computer in the system. The discrete file servers may then be coupled through a device which translates the network protocol of one network into the protocol of another network. This approach requires detailed knowledge of the protocols of both networks. In addition, since file requests are routed through two separate file servers, system performance is reduced.
Another approach to networking diverse computer systems is to provide a single file server and a protocol-to-protocol converter for each foreign client in the system. For example, one common network manufactured by Novell, employs a feature referred to as a "Service Protocol Gateway," or SPG, as part of the overall architecture. The SPG translates the file server protocol of a remote user or client system to the file server protocol of the native file server. This approach has a considerable performance degradation since it also requires that the native protocol be processed. In other words, this approach requires placing a gateway between an existing file server and a foreign client or file server. The gateway performs a translation between the file server protocols of the respective systems. Unfortunately, this method often requires modification of the file servers involved, especially if any significant level of integration is to be achieved.
Still another approach to networking computers involves teaching a file server about an alternate file system by adding knowledge about a particular file server protocol to an existing file server. For example, an IBMPC can be accessed by clients of an Apple LocalTalk network if the IBM-PC is running Apple's network protocol (LocalTalk) and Apple server software (AppleShare). Unfortunately, this method offers no integration of network services. For example, this method allows integration of a foreign client into an existing network but does not allow the foreign client any access to its own user interface or network resources. The foreign client is forced to use the environment of the network it is joining.
The present invention overcomes the above problems by providing a method and means for integration of multiple networks with varying file systems while allowing each client to retain its own native environment in a manner which is totally transparent to users. The present invention also allows many foreign server types to coexist on a single integrated file server while eliminating server-to-server translations, thus improving performance. In addition, the present invention allows a central server to perform network management functions on foreign servers as well as allowing foreign file servers to be added to the system without modifying the central file server.